I like the visuals, but it got me confused several times, especially in caves, but there is something there.
Nice gameplay and UI also.
I know what you mean, maybe it needs more distinct outlines, especially for the passages. I am thinking about how to solve it for the next iteration of this see-through idea, if you have any tips I am all ears :) ...as the player of isometric games this always bothered me so much that the player can't see clearly what the character is seeing, and I am trying to solve this.